Our prior application, Ser. No. 09/303,839, describes a novel electrosurgical handpiece for treating tissue in a surgical procedure commonly known as minimally invasive surgery (MIS). Among the features described and claimed in the prior application is an electrosurgical handpiece that can be used in MIS and reduces the danger of excessive heat causing possible patient harm. This is achieved in one embodiment by an electrosurgical handpiece that is bipolar in operation and that is configured for use in MIS. The bipolar operation confines the electrosurgical currents to a small active region between the active ends of the bipolar electrode and thus reduces the possibility that excessive heat will be developed that can damage patient tissue. Moreover, the position of the active region can be controlled to avoid patient tissue that may be more sensitive to excessive heat. Preferably, the handpiece is provided with a dual compartment insulated elongated tube, each of the compartments serving to house one of the two wires of the bipolar electrodes. The electrode for MIS use is preferably constructed with a flexible end controllable by the surgeon so as to allow the surgeon to manipulate the end as desired during the surgical procedure. In a preferred embodiment, the flexible end is achieved by weakening at the end the housing for the electrode, and providing a pull string or wire connected to the weakened housing end and with a mechanism at the opposite end for the surgeon to pull the string or wire to flex the housing end to the desired position. This feature allows the surgeon to position the active electrode end at the optimum location for treating, say, a herniated disk to remove undesired regions and to provide controlled heat to shrink the tissue during surgery. In FIGS. 3-7 of the prior application, a suitable bipolar electrode is described. FIGS. 8-10 illustrate a suitable unipolar electrode construction of the flexible end handpiece. FIG. 12 illustrates how such an electrode can be used for the reduction of herniated disks in a laparoscopic procedure. FIG. 20 shows a scissors end that can be constructed as a bipolar electrode for certain purposes.
Our prior application, Ser. No. 09/393,286, describes a modified bipolar electrode construction using the flexible end handpiece, the modified bipolar electrode having spaced prongs.
Our prior application, Ser. No. 09/425,313, describes a modified bipolar electrode configured to provide easier flexing of the handpiece end, or more controlled flexing and positioning of the handpiece end.
In these prior applications, the handpiece end is made flexible by providing a spaced set of slots at the handpiece end, such that, when a pulling wire attached to the handpiece end is pulled by the surgeon, the end bends or flexes in a direction toward the slotted side.
The present invention is a continuation-in-part of the three prior applications and hereby incorporates by reference the total contents of the three prior applications, Ser. Nos. 09/303,839, 09/393,286 and 09/425,313. The present invention describes a novel handpiece end construction that offers certain benefits not readily obtainable with the constructions of the prior applications. Since the present application otherwise makes use of the same teachings of the prior applications, it was felt unnecessary to repeat in the body of this specification many of the details present in the contents of the prior application. The present description will be confined solely to the differences in the handpiece ends to achieve certain benefits that may be more difficult to achieve with the constructions of the prior applications. For more details, the reader is directed to the prior applications.
The new handpiece end constructions of the present improvement uses the bipolar principle and are configured to provide more controlled distribution of the electrosurgical currents to the tissue to be modulated.
In a preferred embodiment, the electrode ends are formed by axially-projecting, dual spaced wire loops each connected to a terminal of the bipolar source. In a first preferred embodiment, the wire loops project in spaced parallel planes approximately the same distance from the insulated end of the electrode. In a second preferred embodiment, the wire loops project different distances from the electrode end.
It is also possible within the scope of the invention for the wire loops to lie in spaced non-parallel planes.
The constructions of the invention will provide the same important benefits not only for MIS of herniated disks but also for other MIS procedures where controlled electrode position and controlled heat generation is of importance as described in the prior applications, as well as for general electrosurgical procedures where the volumetric reduction of tissue is desirable.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described the preferred embodiments of the invention.